One of Hawaii's most popular tourist attractions is now requiring out-of-state visitors to pre-book a reservation.

A hike up Diamond Head State Monument is one of the must-dos when visiting O'ahu.

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The area needs a congestion-management plan in order to improve the quality of experiences and reduce the impact on surrounding communities. When a new booking system goes live, visitors from out-of-state will need to make a reservation to enter Diamond Head.

The new reservation system is intended to reduce hiker and vehicle congestion, according to Hawaii's Governor David Ige.

Fourteen days ahead, reservations will need to be made. People without a valid Hawaii driver's license or ID will need to make a reservation to enter the park.

Hawaii residents will continue to enjoy free access without reservations, but entry might depend on the number of parking spaces available on any given day.

The booking system will go live on April 28 and we will update this article with the booking link when it is available.

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Young woman on mountain top arms outstretched, Honolulu, Hawaii, USA
The booking system should promote visitor safety and enjoyment © Getty Images

The creation of reservation systems for natural and cultural sites across the island is part of the new Destination Management Action Plan.

Reducing long lines at the entry and crowding along the trail should be promoted by the booking system at Diamond Head. Diamond Head's natural resources will be better protected if park officials keep visitor numbers in check.

The tourism board said in a press release that the new reservation system will improve the experience of visitors and help preserve the landmark for future generations.

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